TEHRAN (Reuters) – Two thirds of people detained during post-election unrest in Tehran last month have already been freed and another 100 will soon be released, Iranâ€™s police chief was quoted as saying on Wednesday.

â€œOne hundred more will be released in the next two days,â€ state broadcaster IRIB quoted Esmail Ahmadi-Moghaddam as saying in the northwestern city of Qazvin.

The same official last week said 1,032 people were detained in the capital following the disputed June 12 presidential election, but that most had since been let go.

Official results of the vote showing hardline President Mahmoud Ahmadinejad had won by a landslide triggered days of mass street protests by supporters of defeated candidate Mirhossein Mousavi, a moderate who says the election was rigged.

State media say at least 20 people were killed as protesters clashed with riot police and members of the Basij militia. The authorities and Mousavi blame each other for the bloodshed. Hardliners have called for Mousavi to be put on trial.

Rights activists have said 2,000 detained during the voteâ€™s turbulent aftermath may still be held across Iran, including leading reformers, academics, journalists and students.

But a reformist member of parliament quoted Iranâ€™s general prosecutor as saying 2,000 out of 2,500 detained had been freed and that the remaining cases would be referred to the judiciary.

The MP, Mohammadreza Tadesh, was quoted by a reformist website as making the statement on Wednesday after a meeting with the prosecutor, Ghorbanali Dorri-Najafabadi.

Mousavi has demanded the release of â€œchildren of the revolution,â€ referring to many detained establishment figures.

They include a former vice president and other former officials who held senior positions during the 1997-2005 presidency of Mohammad Khatami, who backed Mousaviâ€™s campaign.

The authorities accuse the West, particularly the United States and Britain, of inciting unrest in the Islamic Republic following the election, which led to the most widespread street protests in Iran since the 1979 Islamic revolution.

Security forces quelled the demonstrations but Mousavi and allies have refused to back down, saying Ahmadinejadâ€™s next government would be illegitimate.

The authorities reject vote rigging allegations. Ahmadinejad said on Tuesday it had been the worldâ€™s â€œfreestâ€ election.

Iranâ€™s main moderate party, Islamic Iranâ€™s Participation Front, called on Wednesday for the immediate release of its detained members and other people arrested because of their activities in support of moderate candidates in the election.

In a statement on its website, it expressed deep concern about the health situation of some of those held.

â€œWhatever happens to them, those who in the name of law and sharia arrested them will be responsible,â€ the party said.

The Kargozaran party, seen as close to former President Akbar Hashemi Rafsanjani, earlier this week also called for the release of those detained and rejected the election result.

In Geneva, six U.N. human rights experts sought permission to visit Iran, saying they were concerned that political opponents of Ahmadinejad were continuing to be targeted.

â€œThe legal basis for the arrests of journalists, human rights defenders, opposition supporters and scores of demonstrators remains unclear,â€ they said in a joint statement.

â€œFreedom of expression and peaceful assembly continue to be undermined and the situation of human rights defenders is increasingly precarious,â€ the statement said.